Please note:

PTB stopped its research activities in the field of room acoustics. Thus, the following information is provided without any further support.

The most important requirement for a successful simulation of room acoustic parameters with computer simulation programs is the knowledge of the exact room geometry and above all of  the reflection properties of room limiting surfaces. To give the user and developer in this special field a uniform basis for the last mentioned parameters PTB room acousticians initiated a data collection as EXCEL-file and as compressed zip-file. It has been kept up to date until PTB stopped its activity in room acoustics research. All absorption grades (a ) and - if possible - scattering coefficients (s) known to us are listed and can be downloaded and used as you like. To simulate the reflection properties of sound waves on walls these data are (mostly) needed in octave sectors by room simulation programs. More than 2000 data sets are available.

Recommendation for use:

The user can sort the data with Excel functions by selected criteria: some columns contain functions that deliver interesting criteria for sorting. E.g. fMax contains the octav centre frequency of the maximum value of absorption. This value is displayed in the column a max. Sorting procedure: Choose sheet "selection_table". In columns AK to AW choose criteria according to shown legend. Click on an arrow and then on your chosen code-nr.. Click on button "selection". Sheet "graph" opens and you can take a look at the chosen data by clicking on button "selected data". Further sorting procedures according to the first one are possible. You leave the selection by clicking on button "selection off" . Button "entire data" is available again. Further you can choose "user definable" and define one or more conditions that your problem requires: e.g. fMax = 1000 Hz, or a max < 0.8.

Files provided:

Excel 97 file with absorption data